Process of manufacturing battery-plates



Patented June 14, 19.21.

2 SHEETS-SHEET I.

K. WRTGHT.

PROCESS 0E MANUFACTURING BATTERY PLATES.

APPLICATION FILED JULY 10,1920.

l 4 M A K. WRIGHT.

PROCESS 0F MANUFACTURING BATTERY PLATES.

. PPLICATION FILED IULY I0, I920. 1,381,387. PatentedJune 14, 1921.

UITED STATES PATENT OFFICE.

KENNETH WRIGHT, or

MICHIGAN.

PROCESS OF MANUFACTURING BATTERY-PLATES pplicaton filed July 1G,

T 0 all whom t may concern.'

Be it known that l, KENNETH 1ilfaieri'r, citizenof the United States,residing at F lint, county of Genesee, State ot Michigan, have inventeda certain new and useful `improvement in ldrocesses of ManufacturingBatter 7-Plates, and declare the following to be a full, clear, andexact description of the saine, such as will enable others skilled inthe vart to which it pertains to make and use the same7 reference beinghad to the accompanyingdrawings, Which torni a )art of thisspecification.

lilly invention relates to method of manufacturing or tery plates andconsists in forming a negative electrode in the forming tank, formingnegative plates through the use of dummy positives and then by usingsuch formed negatives in both the negative and positive positions in thebattery, upon the passing of an electric current therethrough, forming apositive electrode, the negative electrode remaining negative.

By this process it ispossible to do away with the use or" forming agentsused to cement the particles of a plate togethe [i more perfectlybuilt-up plate is produced, the particles of which are more securelycemented together and which is capable of delivering Ygreater currentand is of longer life and able to take a'greater charge than is possiblewith the present standard practice. f

In the drawings- Fig'ure l is a plan view showing` the series of platespositioned in the forming tank.

Fig'. 2 shows an enlarged section or' a forming tank.

F 3 is an elevation et' one of the metal ribs.

Fig. 4 is an elevation of a lead dummy plate.

Fig. 5 is a perspective showing' the negative and positive electrodesot' the battery `withdrawn from one another.

Fig. G is a plan vieu' showingf the negative and positive electrodes ofthe battery separated from each other with separator strips positionedbetween such units before they have been assembled.-

Fig. i' is a plan `vieuv showing the two electrodes assembled as in abattery jar with the intervenin separator strips in position.

an improved 'forming bat- Speccation of Letters Patent.

Patented June'let, 1921.

Serial No. 395,261.

` rllhe commercial manufacture of battery plates is, as to certaingeneral practices iairly standardized. To a degree I follow, the generalroutine and it is thought that it will be helpful briefly to set forthsuch practice. then distinguish the ivav in which my method ofmanufacture diff/ers theretrom so as to clearly show what l deem tobe'my invention in the art.

in the manufacture ot' battery plates today, a pasted plate is the basison which the operation starts. These. pasted plates comprise a castingcommonly termed a grid composed ot lead. with a small percentao'eperhaps 8 to 10%, ot antimonv. which ei'jid 1s used as the skeletontrameivork on which to hangl the active7 substance, such as litharge.

ln present day manufacture, these active substances vary in the positiveand negative plates. A standard paste used for the positive plate islitharge (PbG) or red lead .(Pbgtlk.) or a combination of the two mixedinto a paste by the use ot' sulfuric acid diluted with .vater. Lithargealone so mixed into such a paste might be considered a standard pastet'or the negative plate. These pastes are Worked into the interstices otthe plate either by hand or by the use ot' machinery and the plates arethen allowed to harden and they form what is termed a pasted plate.Certain forming agents are frequently used in the paste, such as sugarand magnesium sulfate, etc. These Jtorming argents are to increase thehardness ot the plates or the porosity or for other rea- They. however,form no part ot my plates, negatives and positor the sake otdifferentiating from the completed or formed plates tl have gone througha forming be referred to herein as unplaced in a standimmersed in anelectrotank formed plates, are now ard forming tank. lvte. a ceninionone would be sulfuric acid (H2504) the specific l,f ravity of which isabout 1.2300. 'They are arranged similarly to their arrangement in. abattery, that is positii tire plates connected together and the negativeplates connected together separated from each other and supported fromthe bottom of the tank. An electric current is then passed through for sand negatives alternating, the posiis? ,v

days, positive plates under its l,influence changing to lead peroxidwith a small percentage of litharge and lead sulfate and turning to achocolate brown color, and the negative plates changing to spongy orpure Y metallic lead with a small percentage of litharge and assuming aslate gray color. This process is called forming the plates. T he pasteas originally applied to the grids could not enter into chemical actionswith the electrolyte so as to provide electricity, but must first bechanged by the use of an electric current before becoming activematerial and this change takes place in the forming process in the tank.

I use a similar forming tank indicated as a provided with strips, notshown in the drawing, extending longitudinally along 'the bottom thereofto support the plates therefrom. I provide an acid bath having aspecific gravity of about 1.150 in which the -plates are immersed. I donot, however,

make up positive and negative plates. I make merely negative plates inthe forming tank. My negative plate comprises a grid Z) provided withthe conventional lugs b2 at one end, which are adapted to be secured toa connecting strip c as'shown in Fig. 5. On this skeleton framework Iaffix a paste formed of red lead, a preferred combination being %,redlead and 20% litharge mixed into a paste by the use of diluted sulfuricacid and applied to the plates as described,

These forming a pasted unformed plate. negative plates of a brick redcolor are connected together to form a negative electrode in the formingtank, as shown in Fig. 1 at e and separated from each other and from thepositive dummies by side strips a2, as shown in Fig. 2'.

In place of the positive pasted plates previously described I providedummy metallic lead blanks or plates connected together to form apositive electrode. These dummies are simply metallic lead platesconnected together 1n the forming tank as at f and used in the positiveposition. An electric current is now passed through the plates and thenegative pasted plates change to pure metallic lead with perhaps a smallpercentage of litharge and turn to a slate gray color.

Whatever change takes place in the positive makes no difference as theyare intended for useover again and are merely to be used in the formingtank.

By the use of these lead dummies a heavier current may be sent through,as the electric current is cementing or sulfating the negative platesand whatever breaking down effect this current may have on the leaddummies is of no consequence. Because all my plates are made in thenegative position the active substance is cemented or sulfated to form acompact, hardened plate of a substanti-ally serviceable character. It isnot necessary. therefore, to use any of the many kinds of forming agentssuch as magnesium sulfate to cement the particles of the platestogether. These forming agents as a rule have a harmful effect upon theplate. Furthermore in the manufacture of plates as practised today thereis a great loss of the positives in the forming tank. These are brokendown and ruined due to the action of the electrical current. By notusing the pasted plates in the positive position there is no such lossin my process of manufacture and my negative plates are of superiorcharacter.

When the forming process is completed, the negatives are withdrawn fromthe tank and assembled into units of eight or nine or such number as maybe desired, as shown in Figs. 5 and 6, the lug b2 carried at one endthereof being fused into a connecting strap c as shown in Fig. 5. Thisforms a unit adapted to serve as one electrode in a battery and issimilar to the present practice of assembly. Two of these assembledunits are then immersed in the electrolyte carried in the battery jar,as shown in Fig. 6, where the rubber jar is indicated by letter g andbattery boX by 7L. Suitable separators el are provided lbetween theplates which of course is conventional practice. One unit is connectedto form the positive electrode and the other the negative electrode.

It will be observed, herefore, that in the battery as just described Ihave used the negative plates taken from the forming tank in both thepositive and negative electrodes. The electric cur-rent is now passedthrough the battery and as the charging current passes through thebattery 'plates carried by the unit which forms the positive electrodethey change to positive plates, turning to a chocolate brown color andchanging from pure metallic lead to lead peroxid. The plates forming thenegative electrode remain spongy lead. Upon the completion of thischarging operation the battery is complete, it of course beingunderstood that the further assembly will be completed, such as securinga cover plate to a jar and providing the battery boX. l

It may rove desirable to vary the specific gravity of the electrolyte inthe battery jar after the forming process has been completed byincreasing the amount of the acid.

`What I claim is:

l. The method of forming battery plates which consists in using at thenegative pole in a forming tank a series of pasted plates connectedtogether and at the positive pole a series of dummy lead blanksconnected to-v gether. passing an electric current therethrough for suchtime as is necessary to form such negative plates.

2. The method of forming battery plates which consists in immersing in aforming tank containing sulfuric acid at about 1.150 specific gravity aseries of pasted plates connectedtogether and a series of metallic leadplates connected together, such pasted plates alternating with said leadplates but spaced apart therefrom, passing an electric current throughsaid lead plates, sulfuric acid,.and through said pasted plates untilsuch pasted plates have changed to substantially pure metallic lead.

3. A method of forming battery plates which consists in immersing in anelectrolyte in a forming tank `a series of pasted metallic grids uponwhich a. paste composed largely of red lead has been applied, connectingsuch pasted plates together to form the negative electrode, connectingtogether a series of metallic lead blanks to form the positiveelectrode, alternating the same with the pasted plates and spacing themfrom each other in the usual manneradopted in the forming tank, passing`an electric current therethrough at such rate, strength, etc., as maybe most desirable until the pasted plate has changed to substantiallypure metallic lead and chemical action within the negative plates haspractically ceased.

4. The method of forming which consists in applying to a metallic grid apaste composed of red lead with a considerably less quantity of lithargemixed to form a paste by the use of dilute sulfuric acid, connectingr aseries of such plates together to form the negative electrode in thetank, immersing the same in a forming tank containing dilute sulfuricacid, connecting together a series of metallic lead plates to form thepositive electrode, alternating said lead plates with said pastedpla-tes `and spaced therefrom, passing an electric current through saidlead plates, electrolyte and negative plates for such time as may benecessary to change the negative plates to spongy lead. y

battery plates 5. A method of formin'g battery plates which consists inproviding a pasted plate formed on a skeleton framework of metalliclead, the paste being composed largely of red lead, connecting suchpasted plates together and immers-ing the same in a dilute 2SO4electrolyte in a forming tank, connecting together a series of metalliclead blanks and mmersing the same in said electrolyte so that the leadblanks alternate with the pasted plates but are spaced therefrom, usingthe lead blanks as ythe positive electrode `and the pasted plates as thenegative'electrode in such forming tank, passing an electric currenttherethrough until chemical action within the pasted plates haspractically ceased, removing such formed negative plates from the tanktogethery a series to forni the positive electrode, positioning thesamein a battery jar immersed in an electrolyte therein contained,connecting togethera second, series to form the negative electrode,positioning the same in the battery jar after the usual fashion,

passing a charging current therethrough `until the plates carried at thepositive pole have changed to positive plates.

6. The method of forming battery plates which consists in forming at thenegative electrode in the forming tank pasted plates of substantiallypure metallic lead through the use of dummy lead blanks at the positiveelectrode, removing such formed metal lead negatives, connecting thesame together to form positive and negative electrodes for a battery,

lyte in a battery jar properly separated from 'each other-,passing anelectric current therethrough .until the 'plates carried at the positivepole become positive and have changed.

substantially to lead pcroxid.

In testimony whereof, l sign this specification.

' KENNETH WRIGHT.

and connecting.

immersin T the same in the electrosov

